Effectiveness of Nutrition and WASH/malaria educational community based interventions in reducing anemia in children from Angola
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OPEN Effectiveness of Nutrition
and WASH/malaria educational
community‑based interventions
in reducing anemia in children
from Angola
Cláudia Fançony1,2*, Ânia Soares1, João Lavinha3,4, Henrique Barros2,6 & Miguel Brito1,5,6
We found no published data in Angola regarding the effect of combining nutrition-specific and
nutrition-sensitive approaches in the reduction of anemia in preschool children. Thus, we implemented
a cluster-randomized controlled trial to determine the effectiveness of two educational-plus-
therapeutic interventions, in Nutrition and WASH/Malaria, in reducing anemia. We compared them
to (1) a test-and-treat intervention and (2) with each other. A block randomization was performed to
allocate 6 isolated hamlets to 3 study arms. A difference-in-difference technique, using Fit Generalized
estimating models, was used to determine differences between the children successfully followed in
all groups, between 2015 and 2016. We found no significant differences in anemia´s and hemoglobin
variability between educational and the control group. However, the WASH/Malaria group had 22.8%
higher prevalence of anemia when compared with the Nutrition group, having also higher prevalence
of P. falciparum. Thus, our results suggest that adding a 12-month educational Nutrition or a WASH/
Malaria component to a test-and-treat approach may have a limited effect in controlling anemia.
Possibly, the intensity and duration of the educational interventions were not sufficient to observe
the amount of behavior change needed to stop transmission and improve the general child feeding
practices.
In sub-Saharan Africa, controlling infectious morbidity through drug therapy, alongside increasing micronutrient
intake, has been the most used approach to interrupt the processes by which infectious diseases cause anemia
(such as blood loss, inflammation, hemolysis and blunted intestinal villi) and may increase the impact of health
interventions1–3. However, controlling schistosomiasis, intestinal parasites and malaria exclusively through drug
therapy may have limited sustainability in contaminated environment and/or in settings with inadequate water,
sanitation and hygiene and malaria preventive practices and behaviors, because high re-infection rates may
occur4–6. Thus, an educational component is essential to limit transmission.
A nutrition-sensitive approach could increase hemoglobin based on the assumption that providing health
education and promoting adequate Water, Sanitation and Hygiene and malaria (WASH/Malaria) preventive
practices would lead to improved knowledge and awareness of mothers/caretakers regarding the causes, pre-
vention and treatment of urogenital schistosomiasis, intestinal parasite and malaria. This, would in turn reduce
inadequate practices and risk behaviors (child´s, mother´s and mother-to-child practices) and therefore reducing
iseases5–10.
prevalence, incidence and re-infection rates of those d
Nevertheless, nutrition-specific approaches are crucial to address micronutrient deficiencies caused by inad-
equate Infant and Young Child Feeding Practices (IYCF), which could also benefit from increased sustainability
if combined with a therapeutic approach. A nutrition educational intervention could reduce anemia based on
the assumption that the intervention would improve the knowledge and awareness of mothers and caretakers
1
Health Research Center of Angola (CISA, Translated), Caxito, Angola. 2Instituto de Saúde Pública da Universidade
Do Porto, Porto, Portugal. 3Departamento de Genética Humana, Instituto Nacional de Saúde Dr. Ricardo
Jorge, Lisbon, Portugal. 4BioISI, Faculdade de Ciências, Universidade de Lisboa, Lisbon, Portugal. 5Health and
Technology Research Center (H&TRC), Escola Superior de Tecnologia da Saúde de Lisboa, Instituto Politécnico de
Lisboa, Lisbon, Portugal. 6These authors jointly supervised this work: Henrique Barros and Miguel Brito. *email:
claudia.videira@cisacaxito.org
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regarding adequate feeding practices, which in turn could be translated into behavior changes resulting in
improved nutritional quality of the food consumed by the child. This, could finally be reflected in decreased
anemia and increased hemoglobin l evels11–15.
The overall goal of educational interventions is to empower individuals to improve the quality of their own
diets, and/or WASH and malaria preventive practices16–18. Furthermore, the design of these interventions may
vary according to the target population (adult or children), dimensions of the learning package (e.g. for WASH:
stool disposal, water quality or supply, for malaria prevention: bednet usage and vector control, and for nutrition:
nutritional diversity, consumption of specific micronutrient-rich foods), the delivers (community promoters/
volunteers, teachers, local health workers, community leaders), the place where education occurs (domiciliary,
at the health center or at community classes), the number of intervention contacts, type of contacts (group meet-
ings and/or individual contacts), duration of interventional contacts and the combination with other strategies
(construction of latrines and hand-washing mechanisms, micronutrient supplementation or food fortification
and/or annual or biannual deworming etc.)6,13,14,19–31. Considering that those methodologic variabilities may in
turn influence the outcomes of interventions, studies investigating if a nutrition-sensitive approach can reduce
anemia better than a nutrition-specific intervention must standardize their design to allow comparability.
Previously we have designed a cluster-randomized controlled trial protocol aiming at determining the effi-
cacy of educational community-based interventions in the reduction of anemia in preschool children, namely
1) Nutrition and 2) WASH/malaria education, both combined with a test-and-treat approach32. However, at the
pre-intervention assessment the number of eligible clusters were found to be significantly lower than expected,
the baseline characteristics of the participants were heterogeneous between the groups studied, and difficulties in
assuring that interventions would be implemented under the ideal and highly controlled experimental conditions
were anticipated. In the present study, we transitioned to an effectiveness cluster-randomized controlled trial.
In doing so, small modifications were performed in the previous protocol, mainly in the main objective. Here,
we primarily aim at testing whether a Nutrition and WASH/Malaria educational, community-based interven-
tions were able to reduce anemia in pre-school children from Bengo (Angola), under real-world conditions. A
beneficial point resulting from this design modification is the possibility of understanding if these interventions
can produce effects under ecologically relevant conditions. On the other hand, lower internal validity and gen-
eralizability are expected to be associated to these alterations33. Three main hypothesis are being investigated,
namely: (1) if adding a WASH/Malaria educational component to a test-and-treat therapeutic approach result
in higher reduction of anemia, when compared to an exclusive therapeutic strategy, (2) if adding a nutrition
educational component to a test-and-treat approach result in higher reduction of anemia, when compared to an
exclusive therapeutic strategy, and 3) if the addition of a WASH/Malaria educational component (to a test-and-
treat approach) result in higher reduction of anemia, than the addition of a nutrition educational component.
Results
Participant flow and characteristics. At the end of the census approach, 1106 households were con-
sidered eligible and the ones with the presence of the caretaker at the moment of the census were invited to
participate. Of those, 830 caretakers and 948 children from seven hamlets attended the evaluation day at their
local health centers. Furthermore, before randomization, one cluster was excluded due to a very low number of
eligible resident children (only 5 children); despite that they continued to be followed. The number of partici-
pants randomly assigned to each arm and evaluated is described in Fig. 1.
Despite randomization, we found differences in the baseline characteristics between arms, regarding the
children completing the study. For instance, the control arm had higher proportion of girls and children with S.
haematobium infections, while children in the Nutrition arm had lower mean of hemoglobin levels and higher
proportion of anemia, zinc deficiency, feeding frequency and green leaf consumption. Also, children in the
WASH/Malaria arm had higher prevalence of Iron Deficiency and being infected with at least one intestinal/
urogenital parasite (see Supplementary table S1). These variables were used to adjust the effectivity models for
the heterogeneity in their distribution among study groups.
Dropouts occurred differentially between groups only regarding the mean of zinc levels (p-value = 0.042).
Outcomes and estimation. Our results from crude difference-in-difference models showed no statisti-
cally significant differences between the 3 interventions, regarding the reduction of anemia and increasing of
Hb (see Table 1). Nevertheless, differentiated variations between groups were found to occur in the prevalence
of Iron Deficiency, Zinc deficiency and P. falciparum malaria (Wald chi-square p-value = 0.04, 0.04 and < 0.001,
respectively). Those differences occurring specially between the Control and the Nutrition arms (Wald chi-
square p-value = 0.077, p-value = 0.015 and p-value = 0.001, respectively).
When the regression models were adjusted, for the variables presenting differentiated prevalence profile at
the baseline (and taking the Control arm as the reference), we found that the Nutrition group presented higher
percentual enhancement in the prevalence of iron deficiency and lower enhancement of zinc deficiency and
P. falciparum malaria prevalence (see Table 1). On the other hand, the WASH/Malaria group presented lower
enhancement of zinc deficiency prevalence.
Furthermore, when we compared the adjusted WASH/Malaria educational effect to the Nutrition educational
effect, we observed that children in the WASH/Malaria group had 22.8% higher prevalence of anemia than the
Nutrition group. There were also higher prevalence of P. falciparum malaria and reported feeding frequency.
We found no statistically significant associations between the variations in the outcomes and the number of
domiciliary visits provided (see Table 1).
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1106 Eligible households listed
Enrolment
948 Children present for baseline
assessment 6 Excluded
- 5 resident in an excluded cluster
- 1 without Hb data
942 Randomized
195 Allocated to Control arm 435 Allocated to Nutrition arm 312 Allocated to WASH/Malaria arm
- 350 received 6 counselling visits - 239 received all 6 counselling
Allocation
- 85 received less than 6 counselling visits
visits - 73 received less than 6
- 0 did not received any visit counselling visits
- 0 did not received any visit
4 Lost to follow up 76 Lost to follow up 70 Lost to follow up
- 4 Migration - 20 Unknown location - 8 Unknown location
Follow up
- 17 Deaths - 7 Deaths
- 34 Migrations - 53 Migrations
- 5 Refuses - 2 Refuses
128 Analyzed 311 Analyzed 202 Analyzed
- 128 Anemia, underweight, - 311 Anemia - 202 Anemia, stunting, underweight
wasting and stunting - 310 Stunting and underweight and wasting
- 102 IDA, ID and Zinc - 309 Wasting - 178 IDA and ID
- 83 MDD - 246 IDA and ID - 180 Zinc
- 88 Green leaf and meat - 250 Zinc - 129 MDD
- 85 Feeding frequency - 143 MDD - 141 Green leaf and meat
- 128 Malaria - 163 Green leaf and meat - 132 Feeding frequency
- 132 Feeding frequency - 102 Malaria
Analysis
- 109 Intestinal/urogenital
parasites - 311 Malaria - 167 Intestinal/urogenital parasites
- 102 Inflammation - 250 Intestinal/urogenital parasites - 178 Inflammation
- 252 Inflammation
63 Excluded 48 Excluded 40 Excluded
- All without 12-month - All without 12-month evaluations - All without 12-month evaluations
evaluations
Figure 1. Children follow up flowchart. Hb hemoglobin, IDA iron deficiency anemia, ID iron deficiency, MDD
minimum dietary diversity.
To further understand those results, link them to the interventions and assist with the interpretation, we
performed additional ancillary analysis in each group (from the baseline to 12-month follow up) (described in
Table 2).
Ancillary analysis. Comparing pre‑and‑post intervention moments (baseline to 12‑month follow up varia‑
tions). In this study, an increased hemoglobin level (0.05 g/dl, 0.27 g/dl and 0.13 g/dl, respectively for the Con-
trol, Nutrition and WASH/Malaria arms) and a decreased prevalence of anemia (5.5%, 14.2% and 5.4% lower)
were observed in all study arms, between the baseline and the 12-month follow up (Table 2). However, signifi-
cant increased hemoglobin level and decreased anemia prevalence were only observed in the Nutrition arm.
Iron Deficiency Anemia (IDA) prevalence was found to be significantly reduced, either among the children
in the Control (from 24.5% to 10.8%) and WASH/Malaria arms (from 21.9% to 13.5%), while no significant
reduction on iron deficiency prevalence was observed (among the children with hemoglobin level ≤ 11 g/dl). The
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Type of models Crude models Adjusted model 1 Adjusted model 2
WASH/Malaria vs.
Control vs. WASH/ Nutrition Group with
Comparations Malaria vs. Nutrition Nutrition vs. Control WASH/Malaria vs. Control WASH/Malaria vs. Nutrition Interview score effect
Statistic evaluators Wald chi-square p-value % enhance DDI (p-value) % enhance DDI (p-value) % enhance DDI (p-value) DDI (p-value)
Health primary outcome
Hb (Mean) 0.29 2.0 + 0.151 (0.468) 0.7 0.023 (0.912) − 1.3 − 0.160 (0.371) 0.023 (0.403)
Anemia (% yes) 0.22 − 17.2 − 0.424 (0.273) 0.3 0.263 (0.498) 22.8 + 0.641 (0.050) − 0.048 (0.332)
Health secondary outcomes
IDA (% yes) 0.11 50.5 + 0.468 (0.351) 24.2 + 0.276 (0.606) − 27.3 − 0.228 (0.594) 0.017 (0.776)
Iron deficiency (% yes) 0.04 71.6 + 0.866 (0.032) − 5.3 + 0.278 (0.498) − 47.5 − 0.664 (0.144) 0.088 (0.258)
Zinc deficiency (% yes) 0.04 − 94.9 − 3.336 (0.006) − 103.7 − 2.126 (0.088) 169.5 + 1.194 (0.117) 0.081 (0.411)
Weight (Mean) 0.88 0.6 + 0.258 (0.291) 0.6 + 0.281 (0.253) 0.0 − 0.029 (0.886) − 0.006 (0.843)
Stunting (% yes) 0.29 23.3 + 0.196 (0.610) 40.4 + 0.217 (0.575) 11.8 0.043 (0.89) − 0.041 (0.425)
Underweight (% yes) 0.55 – – – – – – –
Wasting (% yes) 0.44 – – – – – – –
P. falciparum (% yes) < 0.001 − 317.7 − 3.052 (0.001) − 669.0 − 0.637 (0.433) 569.1 2.495 (0.013) − 107 (0.351)
At least one intestinal/
urogenital parasite (% 0.79 − 129.1 − 0.073 (0.867) − 6.9 − 0.316 (0.445) 49.8 0.244 (0.510) − 0.061 (0.301)
yes)
Inflammation (% yes) 0.35 – – – – – – –
Behavior Secondary outcome
Green leaf intake (% yes) 0.66 2,3 + 0.261 (0.516) 15,9 + 0.368 (0.385) 11.7 + 0.103 (0.763) 0.009 (0.874)
Meat cons. (% yes) 0.72 − 12,0 − 0.230 (0.587) − 10,6 − 0.262 (0.516) − 1.1 − 0.058 (0.877) 0.048 (0.358)
Feeding frequency
− 15,4 − 0.345 (0.164) − 15,8 − 0.073 (0.769) 2.6 + 0.416 (0.049) 0.006 (0.864)
(Mean)
MDD (% yes) 0.73 – – – – – – –
Table 1. Effectiveness of interventions in reducing anemia and their associated factors. Hb – Hemoglobin,
IDA – Iron deficiency anemia. *difference-in-difference Wald chi-square, # Moderate-to-severe. Models
1—Yit = β0 + β1 Time + β2 Group + δ (Time × Group) + β3 Gender + β4 Age + β5 Zinc Deficiency + β6 Feeding
frequency + β7 Green leaf intake + β8 At least one intestinal/urogenital parasite + ε. Model 2 (nutrition-
WASH/Malaria) and 3 (nutrition-WASH/Malaria with interview scores)—Yit = β0 + β1 Time + β2 Group + δ
(Time × Group) + β3 interview score + β4 Gender + β5 Age + β6 Zinc Deficiency + β7 Feeding frequency + β8
Green leaf intake + β9 At least one intestinal/urogenital parasite + ε. Bold is highlighting statistically significant
p-values.
reduction of zinc deficiency prevalence was significant in the Nutrition arm, decreasing from 12.8% to 3.6%, from
the beginning to the end of the study (see Table 2). Furthermore, despite that decreased wasting was observed
in the Nutrition arm, the prevalence of stunting was found to increase 14.2% among the children in this group.
Stunting among the children in the WASH/Malaria group also increased (16.8%).
Regarding infections, a significant variation in the prevalence of P. falciparum malaria was observed in all
arms (from 6.3% to 21.1% in the Control arm, from 5.8% to 2.3% in the Nutrition arm and from 1.5% to 6.4% in
the WASH/Malaria arm). Furthermore, the prevalence of children infected with at least one intestinal/urogenital
parasite was also found to increase in all arms (32.1% in the control, 19.2% in the Nutrition and 30.5% in the
WASH/Malaria arm) (see Table 2).
Comparing the 1st and 6th visits for behaviour change. More than 70% of the participants within the educa-
tional interventions successfully received 5-to-6 visits (70.8% of the households in the WASH/Malaria group
and 71.8% in the Nutrition group). Furthermore, statistically significant increase in the proportion of house-
holds with latrine, clean latrines, clean environment and observed clean nails of the caretaker were observed in
the WASH/Malaria group and significant increased weekly consumption of cereals, food from animal sources,
legumes, vegetables, fruits and in the minimum feeding frequency was also observed in the Nutrition group
(supplementary table S2).
Discussion
Results from our crude and adjusted difference-in-difference models suggest that implementing two semesterly
rounds of an exclusive test-and-treat therapeutic approach have no statistical significative difference in reducing
anemia and increasing hemoglobin, that when combining this approach with 6 monthly domiciliary counselling
visits addressing adequate child nutrition or WASH/Malaria practices. Considering the positive results reported
by others, and the fact that our process indicators suggest the occurrence of some degree of behavior change in
both educational intervention groups (supplementary table S2), these effectiveness results could suggest that, 1)
the therapeutic component of the intervention played in fact the major role and educating had a residual effect,
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Control Nutrition WASH/Malaria
Outcomes T0 T2 Dif P value T0 T2 Dif P value T0 T2 Dif P value
Primary outcomes
Hb (Mean
11.2 (1.1) 11.3 (1.3) 0.05 0.706* 11.0 (1.4) 11.3 (1.3) 0.27 0.002* 11.3 (1.4) 11.4 (1.1) 0.13 0.210*
(SD))
Anemia (%
39.1 (50/128) 33.6 (43/128) − 5.50 0.392** 50.5 (157/311) 36.3 (113/311) − 14.2 < 0.001** 38.6 (78/202) 33.2 (67/202) − 5.4 0.215**
yes)
Secondary outcomes – Nutritional state
IDA (% yes) 24.5 (25/102) 10.8 (11/102) − 13.73 0.016** 22.4 (55/246) 19.9 (49/246) − 2.4 0.539** 21.9 (39/178) 13.5 (24/178) − 8.4 0.032**
Iron defi-
12.7 (13/102) 7.8 (8/102) − 4.90 0.359** 14.2 (35/246) 19.5 (48/246) 5.3 0.105** 24.2 (43/178) 18 (32/178) − 6.2 0.185**
ciency (% yes)
Zinc defi-
2 (2/102) 4.9 (5/102) 2.94 0.453** 12.8 (32/250) 3.6 (9/250) − 9.2 < 0.001** 4.4 (8/180) 2.8 (5/180) − 1.7 0.581**
ciency (% yes)
Weight gain
9.2 (2.4) 12.1 (2.3) 2.84 < 0.001* 9.0 (2.5) 11.9 (2.1) 2.9 < 0.001* 9.1 (2.3) 12.0 (2.1) 2.9 < 0.001*
(Mean (SD))
Stunting (%
29.7 (38/128) 37.5 (48/128) 7.81 0.143** 27.4 (85/310) 41.6 (129/310) 14.2 < 0.001** 22.3 (45/202) 39.1 (79/202) 16.8 < 0.001**
yes) #
Underweight
20.3 (26/128) 18 (23/128) − 2.30 0.678** 18.1 (56/310) 15.8 (49/310) − 2.3 0.382** 21.3 (43/202) 14.9 (30/202) − 6.4 0.066**
(% yes) #
Wasting (%
9.4 (12/128) 6.3 (8/128) − 3.10 0.454** 7.1 (22/309) 2.3 (7/309) − 4.8 0.003** 10.9 (22/202) 5.4 (11/202) − 5.5 0.052**
yes) #
Secondary outcomes – infections
P. falciparum
6.3 (8/128) 21.1 (27/128) 14.85 < 0.001** 5.8 (18/311) 2.3 (7/311) − 3.5 0.043** 1.5 (3/202) 6.4 (13/202) 4.9 0.021**
(% yes)
At least one
intestinal/
urogenital 16.5 (18/109) 48.6 (53/109) 32.11 < 0.001** 10 (25/250) 29.2 (73/250) 19.2 < 0.001** 22.8 (38/167) 53.3 (89/167) 30.5 < 0.001**
parasite (%
yes)
Inflammation
51 (52/102) 41.2 (42/102) − 9.80 0.174** 39.3 (99/252) 40.5 (102/252) 1.2 0.850** 48.9 (87/178) 44.9 (80/178) − 3.9 0.494**
(% yes)
Secondary outcomes – Feeding practices
Green leaf
12.5 (11/88) 29.5 (26/88) 17.05 0.014** 31.9 (52/163) 49.7 (81/163) 17.8 0.002** 17.7 (25/141) 37.6 (53/141) 19.9 < 0.001**
intake (% yes)
Meat con-
sumption. (% 39.8 (35/88) 27.3 (24/88) − 12.50 0.117** 33.7 (55/163) 17.2 (28/163) − 16.6 < 0.001** 42.6 (60/141) 25.5 (36/141) − 17.0 0.003**
yes)
Feeding
frequency 57.6 (49/85) 75.3 (64/85) 17.65 0.014** 70.5 (93/132) 77.3 (102/132) 6.8 0.243** 59.1 (78/132) 67.4 (89/132) 8.3 0.177**
(> = 3)
MDD (% yes) 13.3 (11/83) 16.9 (14/83) 3.61 0.664** 9.1 (13/143) 7.7 (11/143) − 1.4 0.824** 17.1 (22/129) 17.1 (22/129) 0.0 1.000**
Table 2. Variation in the primary and secondary outcomes among children completing the study, between
the baseline and 12-month follow up. SD – Standard deviation, Hb – Hemoglobin, MDD – Minimum Dietary
Diversity * Students’ t, ** McNemar Test. Bold is highlighting statistically significant P values.
or 2) not all educational actions have been translated into changed behavior and in consequence the needed
sequence of beneficial results happened incompletely (see supplementary Figure F1 and F2) and/or 3) the educa-
tional actions lacked the required intensity (number of monthly visits and duration of each session) and duration
of the educational actions (only 12-months) to translate into significant changes at the primary o utcomes34,35.
In fact, the way educational interventions are expected to impact in the primary outcomes constitute a long
and complex pathway of actions, that may be subject to effect modifications among different populations. For
instance, the therapeutic component (implemented in all study arms) was expected to clear infections that could
be causing anemia; further allowing educational interventions to either improve WASH/Malaria practices that
could reduce the infection transmission and allow the natural recovery of hemoglobin (in the WASH/Malaria
arm); or to improve feeding practices that could lead to higher quantity and quality of diet and improve the
hemoglobin status of children in the absence of infections (in the Nutrition arm). Nevertheless, at the end, all
tree interventions were expected to increase hemoglobin levels and reduce anemia prevalence, besides improv-
ing other nutritional outcomes between the pre- and post-evaluation moments. Thus. plausibility arguments are
recommended to be used as evidence of impact when evaluating the effect of real-world complex i nterventions36.
Accordingly, we have analysed our data by protocol, rather than by intention to treat, to allow combining different
types of evidences able to assist the interpretation of our results and to provide a more comprehensive discussion
following the assumption mentioned a bove37.
For instance, instead of observing reduced prevalence of infections over a 12-month period (between the
baseline and the 12-month follow), we observed a significant increase in the prevalence of having at least one
intestinal/urogenital parasite (mainly G. lamblia, S. haematobium and A. lumbricoides) in all arms, and in the
prevalence of P. falciparum malaria among the children within the Control and WASH/Malaria arms, contrary
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to other studies4,6,25,29,38,39. Assuming that baseline infections were cleared by the test-and-treat approach, this
may associate with the occurrence of frequent/repetitive contact of children with highly contaminated environ-
ments, in turn influenced by the children age (as the wider mobility of older children may increasingly expose
them to sources of contamination), which the WASH educational component wasn’t able to p revent16,40. That is
corroborated by the similar longitudinal infectious profile of both Control and WASH/Malaria arms, and by the
absence of significative differences in those variations in regression models. In the literature, while some studies
report that adding chemotherapy to health education and sanitation can reduce the prevalence, intensity and/or
incidence of A. lumbricoides, T. trichiura, hookworms or schistosomiasis and improve the knowledge, attitude
and preventive practices toward those infections, others report no significant e ffect6,25,26,29. Similarly, malaria,
educational packages were mentioned to improve the knowledge and preventive practices and treatment-seeking
behavior, while integrating community case management and the possession of nets were reported to lower the
prevalence and incidence of fever in under-five years old c hildren8,27,28,41.
Also, adjusted models showed that the Nutrition group had significantly less P. falciparum prevalence than
the Control group. This, could be related to seasonal malaria and ecological conditions35,42. Interestingly, the
Nutrition group had also less zinc deficiency and more iron deficiency (consistent in crude models). To note
that zinc is a trace element associated to the nutrition-dependent immune response (also called as nutritional
immunity), being confined into cellular compartments during inflammatory events to decrease its concentrations
and bioavailability to the pathogen43–45. Also, zinc levels can affect both tissue and/or systemic level responses to
iron deficiency (affecting local iron regulatory proteins and/or the normal function of an iron regulatory hor-
mone called hepcidin)44,46–53. Thus, we speculate that the reduction of P. falciparum malaria and zinc deficiency
prevalence may have influenced each other, in turn affecting the prevalence of iron deficiency. Nevertheless, our
results don’t allow to determine to which extent the educational approaches could have contributed differently
to this fact.
Regarding the effect of educating for adequate IYCF practices, despite that a significant increase in the preva-
lence of reported consumption of green leaf in the previous 24 h (18.2%) was documented between the baseline
and the 12-month follow up, children at the Nutrition group were reported to have consumed significantly less
meat (− 16.9%) and lower feeding frequency (− 0.26) at the end of the study, when compared to the baseline.
Additionally, the intervention failed at increasing the prevalence of Minimum Dietary Diversity (MDD) observed
at the baseline. Those facts suggest that the educational component of the intervention may have had positive
impact in some behavioral secondary outcomes but not in all of them (assumptions supported by our process
indicators described in supplementary Table S2). Others reported that educational programs in nutrition may
lead to children being fed more green leafy vegetables, nutrient-dense thick foods at lunch and meeting the
dietary requirements for energy, iron and zinc more frequently and improved ability of mothers to identify
malnutrition, despite that methodological variations may lead to different r esults11,13,20,21.
Two main operational limitations must be considered when interpreting our results. First, relates to the limita-
tions documented during the implementation of the Test-and-Treat approach (performed in all study groups).
Here, limitations in the implementation of the active screening and treatment of infections in the community
was associated to failure to obtain samples (or to obtain the needed volume), samples collected in inappropriate
containers (which may have introduced contaminations and misestimated frequencies), impossibility to perform
Kato Katz in diarrheal samples (limiting the diagnosis of helminths), diagnosis made from single samples, failure
of caretakers/children’s to attend treatment visits or consultations, non-supervision of all therapeutic dosage
intake, difficulty in relocating households, and inadequate filling of treatment records by technicians (making
the success of some treatments being inconclusive). Secondly, providing bed nets, soap and bleach to all groups
may have encouraged caretakers to use it, potentially confounding the results of the Control and Nutrition arms.
There was variation in the infectious profile of each cluster and that should also be taken into consideration.
It is reported that when moving from efficacy to effectiveness studies, we may also move to lower degree of
generalizability33,36. Here, considering that randomization did not produced absolutely comparable groups, as
differences regarding some baseline characteristics were observed between groups (i.e. the prevalence of some
outcomes was not diluted within the clusters), generalizability is l imited54. Thus, we recommend that the inter-
pretation of results should be restricted to our settings and study populations. Furthermore, to use the difference-
in-difference analysis in groups differing significantly at the baseline may wrongly suggest that changes occurred
in one group and not in the o ther55. To minimize the impact of that issue in our results, we have adjusted the
difference-in-difference models, accounting for variables whose baseline prevalence or value was statistically
different between the groups being compared, as performed by others in similar studies (see supplementary
Table S1)56. When interpreting our results, the reader must also consider that we have used a fixed number of
clusters (of fixed size), and that it is reported that when the results of cluster randomized trials (with less than
40 clusters), are analysed using generalised equations there is an increased risk of inflated type I error (i.e., false
positive findings)55. Nevertheless, some design aspects, commonly associated with efficacy research studies, were
sustained in the effectiveness study implemented here, such as standardized design, structured interventions,
focus on specific primary outcomes (while the improvement in behavior was kept as a secondary outcomes) and
randomized assignment to interventions were still being implemented. Thus, our study may represent a hybrid
between efficacy and effectivity, potentially allowing for a more systematized (real-life intervention) results,
comparatively to traditional effectiveness studies.
Methods
All methods in this study were carried in accordance to relevant guidelines and regulations, following both
national regulatory norms and standards, as also international recommendations.
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Trial design. This study is a open (unblinded), parallel, cluster-randomized controlled trial, with 3 arms.
Participants. Eligibility criteria. Children younger than 3 years old, resident in the selected hamlets, who
were evaluated at the pre-intervention assessment, were considered eligible.
Recruitment, follow up and counselling visits. The initial assessment of participants occurred between March
and May of 2015 (baseline that included 948 children), while the follow-ups occurred between November and
December 2015 (6-month follow up that included 524 children) and between July and August of 2016 (12-month
follow up that included 660 children). The counselling moments have intercalated those evaluation moments in
2 rounds of 3 counselling visits. The first occurred between June and October 2015 (included 610, 576 and 574
of the caretakers) and the second round occurred between January and June of 2016 (included 561, 574 and 563
of the caretakers).
Settings and locations where the data were collected. The data was collected in 7 administratively
and geographically isolated hamlets with health facilities, located within the CISA Health and Demographic Sur-
veillance System (HDSS) study area, and that were found to provide daily primary care at the pre-intervention
assessment. The DHSS area comprehend essentially the communes of Úcua, Caxito and Mabubas, in turn located
within the Dande municipality of the Bengo province (in Angola). Detailed characterization of demography,
socioeconomic aspects, causes of death and epidemiology of some diseases have already been p ublished57–65.
Interventions. Therapeutic (test‑and‑treat) component. This component was included in all study arms
and was conducted and implemented at the evaluation moments. Briefly, P. falciparum infections were screened
and treated at the evaluation sites, while urogenital schistosomiasis and/or intestinal parasites were diagnosed at
the CISA´s laboratory and treated at specific domiciliary visits (in the case of treatments with albendazole) and/
or hospital-based consultations (in the case of treatments with praziquantel)32. A standard treatment protocol,
following the national therapeutic guidelines and specific bibliography, was used. Furthermore, children diag-
nosed with sickle cell disease were referred to the Anemia Patient Follow-up Consultation, held at the Bengo
General Hospital.
Educational component. As previously published, caretakers of children allocated to the educational interven-
tions in Nutrition or WASH/Malaria have received six domiciliary, personalized counselling sessions32. Those
educational visits were conducted from June of 2015 and June of 2016), having 3 evaluation moments being
implemented before they start (at the baseline), after 3 of those visits (first follow up) and after the sixth visit (sec-
ond follow up). Briefly, counselling to the educational intervention groups targeted eight main topics. Regarding
the nutrition group, the main topics were breastfeeding, complementary feeding, weekly adequate food diversity,
appropriate number of meals, adequate amount of food, responsible feeding, food and disease, and food safety
and hygiene. On the other hand, the WASH/Malaria group was counselled on insecticide-treated nets (ITNs)
usage, reducing mosquito breeding sites, prevention of open sky defecation, latrine cleaning, adequate hand
washing, healthy backyard environment, adequate water availability, treatment, transportation and storage and
adequate personal hygiene as previously described32.
Socio‑economic and demographic data and biological specimen collection and laboratory
testing. The sample collection and processing have been previously described in d etail32. Briefly, a stand-
ardized questionnaire was administered by trained interviewers to mothers or caretakers, aiming at collecting
socio-economic and demographic information, as well as information regarding pregnancy and breastfeeding,
complementary feeding practices, health care, food security, WASH and malaria p ractices66,67. Weight, height
and mid-arm circumference were measured and used to calculate anthropometric indices for the diagnosis of
undernutrition, according to WHO s tandards68. Blood was collected by venous puncture according to WHO
recommendations for neonates and young children and used for 1) the diagnosis of P. falciparum, through Rapid
Diagnostic Tests (SD bioline Malaria Ag P.f/P.v, Standard Diagnostics, Inc., Republic of Korea) and 2) biochemi-
cal analysis for the quantification of blood levels of hemoglobin (using an Hemocue Hb 301 System, Angel-
holm, Sweden) and serum levels of ferritin, Protein-C- Reactive and Zinc (using an automated autoanalizer
(BT1500) from Biotecnica Instruments S.p.A, Rome, Italy) and CRP turbidimetric latex, Ferritin and Zinc kits
from Quimica Clínica Aplicada S.A., Tarragona, Spain)69. The diagnosis of intestinal parasites in stool samples
was performed using Kato-Katz technique and Parasitrap kits (Biosepar, Germany) and urogenital schistoso-
miasis was diagnosed by urine filtration, using Whatman Nuclepore membranes (diam. 25 mm, pore size 12 μm,
polycarbonate, Merck, Germany)70–72.
Outcomes. Primary outcomes comprised only health indicators, namely increase in hemoglobin levels and
reduction of anemia prevalence, as described by Fançony et al. 2 01932. Secondary outcomes comprised health
and behavior indicators for the estimation of impact evaluations, while process indicators (which comprised
either reported or observed practices or behaviors collected at the counselling visits) were used to conduct pro-
cess evaluations. The complete list of outcomes and their analysis strategy within each arm is presented Table 3.
Sampling strategy. The sampling strategy chosen for this study was a non-probabilistic (convenience)
sampling32. Eligible children were listed and invited to participate using a census approach, within a fixed num-
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Variables WASH/Malaria Nutrition Control
1) Primary outcome:
1.1) Impact on health measured at the evaluation moments*
Hemoglobin levels (g/dl) x x x
Anemia prevalence (%) x x x
2) Secondary outcomes:
2.1) Impact on health measured at the evaluation moments*
Iron deficiency anemia (%) x x x
Weight (kg) x x x
Stunting (%) x x x
Underweight (%) x x x
Having at least one intestinal/urogenital parasite (%) x x x
P. falciparum (%) x x x
2.2) Impact on behaviour reported at evaluation moments*
Minimum dietary diversity (MDD) (%) x x x
Green leaf consumption (in previous 24 h) (%) x x x
Meat consumption (in previous 24 h) (%) x x x
Children sleeping under bednets in the previous night (%) x x x
2.3) Impact on behaviour observed by the technician at the WASH/Malaria educational sessions**
Nº of domiciliary counselling visits delivered (%) x NA NA
Having bednet in the children’s bed (%) x NA NA
Latrine ownership (%) x NA NA
Having water to wash hands in the latrine (%) x NA NA
Clean latrine (%) x NA NA
Backyard environment with garbage (%) x NA NA
Backyard environment with loose animals (%) x NA NA
Backyard environment with still water (%) x NA NA
Caretaker having clean nails (%) x NA NA
2.4) Impact on behaviour: reported by caretakers at the nutrition educational sessions**
Nº of domiciliary counselling visits delivered (%) NA x NA
Weekly cereal consumption (%) NA x NA
Weekly seeds consumption (%) NA x NA
Weekly Milk and derivatives consumption (%) NA x NA
Weekly Food from animal sources consumption (%) NA x NA
Weekly Eggs consumption (%) NA x NA
Weekly Legumes consumption (%) NA x NA
Weekly Vegetables consumption (%) NA x NA
Weekly Fruits consumption (%) NA x NA
Feeding frequency (%) NA x NA
Table 3. Outcomes and analysis performed in this study. x Evaluated; *Mean and frequency variation between
baseline and the 12-month follow up; ** frequency variation between the first and the sixth counselling visits;
NA – Non applicable.
ber of clusters. This strategy was adopted because variations in the density of eligible children were expected and
the real density in each cluster was uncertain.
Randomization. For this study we used a block randomization, where hamlets (considered as cluster units)
were randomly allocated to each study arm. At the end of the pre-evaluation assessment, only 6 hamlets were
found to be eligible and were randomized to the study arms. For the randomization, the names of the hamlets
were written down on pieces of paper, placed in a bag and successively removed. The first two papers removed
were attributed to the Nutrition arm, the following two to the WASH/Malaria arm and the next pair to the con-
trol arm. This process was carried out by the study researchers.
Statistical analysis. SPSS software (version 25.0, International Business Machines Corporation, Pitts-
burgh, PA) was used for statistical analyses.
Prevalence was calculated as the frequencies of the outcome over the total number of samples with valid
results and prevalence reduction (PR) was calculated as the difference between the proportion of prevalence at
the baseline vs 12-month after the beginning of the study.
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To investigate the differences in the baseline characteristics, between the children completing the study and
the ones dropping out after 12-months, we used Chi-square Test for the categoric variables and T Student for
the continuous variables. Logistic regression models were used to analyze interactions between the study arms
and variables (using dropouts as dependent variables) and determine if losses were differentiated between arms.
Thus, the existence of differences in the baseline characteristics between study arms (for children completing
the study) was investigated using ANOVA and Chi-square, respectively to continuous and categoric variables.
Students’ t and McNemar tests were used to determine longitudinal variations on the primary and secondary
outcomes between baseline and the end of the study (respectively at the pre and post-interventional moments)
within each arm.
To determine the differences in the crude variations between the three study arms, the difference-in-difference
technique was performed using Fit Generalized estimating models. In summary, linear regression models were
used to estimate the mean hemoglobin level and weight variations and logistic regression models were used to
estimate the variation on the prevalence of anemia and other secondary binary outcomes. In each model, inde-
pendent variables were time (0 = T0 and 1 = T1), the group, and group*time interaction. Outcomes presenting
significant longitudinal variations within each arm, or significant crude differences when comparing study arms,
were selected to be further inspected for significant differences in adjusted models. Adjustment was conducted
by including secondary outcomes whose prevalence was found to be differentially distributed among the three
arms at the baseline (considered as potentially confounding variables) and also age (found to influence the occur-
rence of anemia in previous studies). The interaction term (represented by DDI) indicates whether there were
statistically significant differences in the adjusted variation of T0 to T1 between groups, as previously described
by Mahfuz et al.56. The Control group was used as the reference group when determining the effectiveness of
the therapeutic-plus-educational intervention, comparatively to an exclusive therapeutic (test-and-treat) inter-
vention, while the Nutrition group was used as the reference group when determining the effectiveness of the
WASH/Malaria educational intervention (further accounting for the number of interviews conducted in both
educational interventions). The quantification of the crude percent of enhancement in the haemoglobin level
and in the prevalence of anemia and associated factors was calculated as described by Mahfuz et al.56.
Process indicators were collected at every counselling visits (from a total of six visits) conducted in Nutrition
and WASH/Malaria arms. Changes in the proportion of adequate behaviour or practices were calculated between
the first and the sixth visits, using McNemar tests. Adequate household behavior/practices in the WASH/Malaria
arm included observed bednet in the children’s bedroom, clean latrine, latrine with water to wash hands (either
with current or still water mechanisms), clean backyard environment, namely without garbage, loose animals,
still waters and caretaker with clean nails. In the Nutrition group, adequate behavior/practices included the
reported weekly consumption of cereals, seeds, milk and milk derivatives, food of animal origin, eggs, legumes,
vegetables, other fruits and the minimum feeding frequency. “Sustained behavior/practice” was considered to
be a behavior or practice observed in both first and sixth visits and “Changed behavior” was considered to be an
altered behavior or practice between the first and sixth visits.
Ethical considerations. After the explanation of the study, an informative brochure was given to the care-
takers. This informative document was illustrative to allow for easy comprehension. Illiterate caretakers were
encouraged to additionally ask for a carefully reading the content of the document at home by a literate family
member and to further ask for additional information at any point of the study. Thereafter, they were asked to
sign an informed consent in order to formalize their acceptance and commitment in their children participa-
tion. The collected data were computerized and archived to ensure the confidentiality and privacy. Children
with positive for malaria, urogenital schistosomiasis and intestinal parasites diagnostic tests were treated with
Artemether-Lumefantrine, albendazole (ALB) and Praziquantel (PZQ) at the baseline, and 6 and 12 months
follow ups (according to a therapeutic protocol approved by a pediatrician and the director of Bengo General
Hospital). Follow up consultations were scheduled for children with severe undernutrition at the malnutrition
department at the Bengo General Hospital and children with severe anemia were forwarded to the pediatric
emergency department of that hospital. Mothers not taking their children to those consultations were visited
to understand the reasons for that and to explain to them the importance of their compliance. This study was
approved by the Angolan Ministry of Health Ethics Committee.
Harms. No harms have been documented during the implementation of this study.
Registration. This study is registered with the title: Efficacy of community educational interventions in
nutrition and WASH/Malaria in reducing anemia in under 5 children, in the municipality of Dande – Angola,
at www.isrctn.com (https://doi.org/10.1186/ISRCTN18101157), with the trial identifier number ISRCTN:
18101157. The date of registration is 06/09/2016.
Protocol. The original protocol can be assessed at https://www.ncbi.nlm.nih.gov/pubmed/30764549.
Conclusions
In this study, adding a 12-month educational Nutrition or a WASH/Malaria component to a test-and-treat
approach had no greater beneficial effect reducing the prevalence of anemia and increasing the level of hemo-
globin than an exclusive therapeutic approach. Possibly, the intensity (number of counselling visits and length
of each session) and duration of the educational actions may haven’t resulted in the amount of behavior change
needed to stop transmission or improve the general child feeding practices, as reported by others, and should
be addressed in future studies. Nevertheless, this is the first study published in Angola simultaneously testing
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the effect of three main strategies to prevent and reduce anemia. Besides comparing the performance of these
interventions in reducing anemia in this context, which allows for evidence-based planification of future tar-
gets, this study also provides detailed data on how the frequency of immediate determinants varies under each
intervention during a 12-month follow up. Considering that anemia and undernutrition had similar proximal
determinants, the application of these results may have broader public health application.
Received: 27 April 2020; Accepted: 13 January 2021
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